A hole in the center of the aluminum (Al) alloy was processed to compensate for the mechanical properties of resistance welded joints of the carbon fiber reinforced epoxy resin matrix (CF/Epoxy) laminate and Al alloy for solving the problem of poor bonding quality in the center of the joint due to uneven temperature distribution in the resistance welding process. The resistance welded lap configuration of the upper Al and the lower laminate was employed, and through holes with a different diameter (dh) were prefabricated on the upper Al alloy plates. The molten polyetherimide (PEI) resin was bonded to the surfaces of the samples on both sides under the action of Joule heat, and the excess PEI resin filled the prefabricated through-hole of the Al alloy plate under pressure and realized the jointing of the 6063Al alloy plate and the CF/Epoxy laminate. The micro-morphology of the welded interface was characterized by scanning electron microscopy (SEM), and the heat distribution of the sample was simulated using COMSOL. The tensile shear force of the joint was tested, which rises with an increase of dh. The failure interface was analyzed in detail, which showed a strong correlation with dh.

Thermosetting composites are widely used in structural parts of aerospace industry. The research of thermosetting composites is also developing continuously, but the connection modes of thermosetting composites needs to be innovative. Mechanical fastening, adhesive bonding and melt welding are the commonly used connections. However, mechanical fastening and adhesive bonding have many disadvantages. Such as drilling, it not only makes fiber fracture, but also destroys composite materials. In adhesive bonding, surface treatment and bonding cycle need a lot of manpower. As time goes by, the bonding strength of the joint gradually decreases. Welding technology has great advantages in assembling and joining thermoset composites (TSC). Different from other review papers, this paper mainly discusses two methods of the surface of the Thermoset composites laminate to be coasted with a thermoplastic layer for the main welding method (resistance welding, ultrasonic welding), Thermoplastic hybrid interlayer and Thermoplastic film co-cure. The problem of thermal degradation of Thermoset composites in welding is discussed.

Recently resistance welding (RW) technique have emerged as a viable alternative method for the joining of fiber reinforced polymer (FRP) composites. It is more cost-efficient as opposed to the conventional adhesive, mechanical and other joining methods. The objective of this paper is to provide a deeper insight into the recent development of the resistance welding technique for FRP composites. The main focus is set on the parameters that govern the welding process and the principal phenomena that affect the joints of the thermoplastic composite. The evaluation methods, the comprehensive failure modes, welding interface behavior and microscopic evaluation of interface are also looked at in detail. And this technology has been further extended to the connection of thermoset composites. In addition, several alternative fresh implants that involve micro-nano carbon materials and offer possibilities for future applications are systematically compared. Continuous resistance welding (CRW) is briefly introduced as one of the most promising methods in the end.

The surface of stainless-steel (SS) mesh was modified by growing carbon nanotubes (CNTs) from ethanol flame. The CNT-modified SS mesh was then used as a heating element for the resistance welding of glass-fibre-reinforced polyetherimide (GF/PEI) laminates to improve the interfacial bond strength of SS wire and PEI resin. Interfacial microstructure, the mechanical properties of the welded joint and the effects of CNT growth time (tg) on the wettability of PEI resin solution to SS wire were investigated. The results indicate that the addition of CNTs increased wettability due to the capillary action of high-porosity CNT coating. The microstructure of the welded joints changed with tg, and the thickness of the welding implant layer decreased below tg = 10 min, and the maximum single lap shear strength (SLSS) value of the welded joint was 39.2 MPa when tg = 10 min. The strengthening mechanism of CNTs and the failure modes of the welded joints were also elucidated in detail by the interfacial shear strength (IFSS) between SS wire, PEI resin and the fractography analysis.

PEI/GF lamination and TI6AL4V alloy are often related to the poor wettability of PEI to TI6AL4V alloy at the interface layer. To overcome these problems, an in situ synthetic candle soot reinforcing coating on TI6AL4V alloy was added into the place of the bonding area. The mechanical properties of composite joints were evaluated by single lap shear strength (LSS) tensile test. The mechanism of strengthening TI6AL4V-PEI/GF joint by candle ash was compared.

研究表面接枝碳纳米管(CNTs)的电阻焊发热元件对热固性复合材料焊接头的增强作用.利用玻璃纤维增强聚醚酰亚胺(GF/PEI)薄片制备表面塑化的碳纤维增强双马树脂(CF/BMI)层合板;继而利用表面接枝CNTs的不锈钢网作为电阻焊的发热元件进行焊接.对接枝不同处理时长CNTs的不锈钢网的焊接件进行单搭接拉伸剪切实验,以评估焊接头的强度.结果表明:不锈钢网表面的浸润性明显改善,焊接头的强度得到显著提升.断口分析显示,在CNTs的增强作用下,失效模式由被焊接件表面纤维的轻微破坏转变为塑化薄层的完全撕裂.

As high-performance and lightweight materials, such as aluminum alloy and titanium alloy, metals are still used in aerospace and aircraft industry. Therefore, the bonding process of composite materials and metals is one of the key issues to be urgently solved and developed in the aerospace industry. Therefore, the connection technology of CFRP to metal is reviewed in this paper. The implementation process of laser welding, friction welding and resistance welding and the types of connection materials are summarized.